When attempting to call a process model exposed as a web service via the webserv

When attempting to call a process model exposed as a web service via the webservicequery() function in Appian 7.6 and 7.7 we are receiving an error. This is the simplest case model (only a start and end node) exposed as a service. The Process Model kicks off as it should, but when the result comes back Appian can not handle it... Below is the call and response, to replicate it all that needs to be done is to create a Process Model simply with a start and an end node (no params or anything) and expose it as a web service.

Expression to invoke service (need to put in real user name and password:
= webservicequery(
a!wsConfig(
wsdlUrl: "localhost:8080/.../CallWebService
service: "{appiancorp.com/.../pm}CallWebService",
port: "StartProcessIFPort",
operation: "{appiancorp.com/.../pm}start"
),
{
startRequest: {
username: "xxxxxx",
password: "xxxxxx"...

OriginalPostID-135034

OriginalPostID-135034